x86: apic_is_clustered_box for vsmp

quad core 8 socket system will have apic id lifting.the apic id range could
be [4, 0x23]. and apic_is_clustered_box will think that need to three clusters
and that is larger than 2. So it is treated as a clustered_box.

and will get:

   Marking TSC unstable due to TSCs unsynchronized

even if the CPUs have X86_FEATURE_CONSTANT_TSC set.

this quick fix will check if the cpu is from AMD.

but vsmp still needs that checking...

this patch is fix to make sure that vsmp not to be passed.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h
index bcfc07f..f0321a4 100644
--- a/include/asm-x86/apic.h
+++ b/include/asm-x86/apic.h
@@ -51,12 +51,17 @@
  */
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
+extern int is_vsmp_box(void);
 #else
 #define apic_write native_apic_write
 #define apic_write_atomic native_apic_write_atomic
 #define apic_read native_apic_read
 #define setup_boot_clock setup_boot_APIC_clock
 #define setup_secondary_clock setup_secondary_APIC_clock
+static int inline is_vsmp_box(void)
+{
+	return 0;
+}
 #endif
 
 static inline void native_apic_write(unsigned long reg, u32 v)